Microprocessor Evolution

The 4004 CPU was the forerunner of all of today’s Intel offerings and, to date, all PC processors have been based on the original Intel designs. The first chip used in an IBM PC was Intel’s 8088. This was not, at the time it was chosen, the best available CPU, in fact Intel’s own 8086 was more powerful and had been released earlier. The 8088 was chosen for reasons of economics: its 8-bit data bus required less costly motherboards than the 16-bit 8086.

Also, at the time that the original PC was designed, most of the interface chips available were intended for use in 8-bit designs. These early processors would have nowhere near sufficient power to run today’s software.

The table below shows the generations of processors from Intel’s first generation 8088/86 in the late 1970s to the eighth-generation AMD Athlon 64, launched in the autumn of 2003: